Field of the Invention
The invention relates to a multipolar plug connector assembly with a plug and a plug connector or matching plug for signal lines conducting digitized electronic signals, wherein the plug connector has a housing in which a number of contact springs at least corresponding to the number of signal lines is disposed and the plug connector cooperates with the plug in such a way that when they are plugged together, on one hand contact is made and on the other hand the contact springs are lifted from a position of rest into an operating position.
Commercially available jacks, such as are customarily employed in connection with telephones, are provided with a plurality of signal lines. When inserting the plug, which can be placed in the jack in a form-locking manner and locked in, contact strips or contact pins of the plug are brought into contact with the contact springs and the electrical connection is made in that way. A form-locking connection is one which connects two elements together due to the shape of the elements themselves, as opposed to a force-locking connection, which locks the elements together by force external to the elements. In the course of such a connection, the contact springs are elastically deformed to generate the contact pressure required for a low-voltage connection. The contact springs are displaced by that deformation. Such a plug-in connection is sufficient for analog signals, such as are used in a telephone. However, if such a plug connector is to be used for making electric connections in which the signal lines carry digitized signals, interference can occur, which is the result of high-frequency signals picked up by transmission lines. The reason therefor is that "pulse-type" signals are used when transmitting digital signals, which generate harmonic interference signals. It is known from the field of oscillation theory to split such pulses into a sequence of sinusoidal oscillations with upper harmonic waves of rising frequencies (harmonic or Fourier analysis). Particularly high harmonics occur if the pulses have steep slopes. With rise times in the range of 1 ns, harmonics are generated which lie at f.sub.c =0.35.multidot.Tr.sup.-1 and therefore at 350 MHz. In that way signal lines of computers can carry signals having harmonics which lie in the range of Megahertz and even as high as Gigahertz. Such higher harmonics can then result in difficulties because of superposition, particularly if several linked electronic data processing installations generate such pulses in a room so that their higher harmonics can interfere with each other in such a way that the problem-free operation of a computer, for example, becomes questionable. Filters are required to keep such superpositions within limits by weakening the unwanted higher harmonics without changing the data signal in an undesirable manner. A capacitor is a circuit element suited for achieving that goal, because its leakage resistance is reversely proportional to the frequency. It goes without saying that such filter connectors are intended to offer protection in particular against interference pulses coming from the exterior, such as electro-magnetic pulses EMP or transmission of radio frequency pulses RFI.